Gaseous fluid distributing system for furnaces and the like



c. B. ARNOLD Erm. 2,528,292 GAsEoUs FLUID nxsTRIBUTING SYSTEM FOR FuRNAcEs AND THE LIKE 4 5 Sheets-Sheet 2 oct. 31, 195o Filed March 27 1946 Kom n2 20m@ INVENTOR. l CHARLES B. ARNOLD. HOWARD F. LAWRENCE.

Wl M L Lw( ATTORNEYS.

Oct. 31, 1950 c. B. ARNOLD ETAL GAsEous FLUID DISTRIBUTING SYSTEM FOR FURNACES AND THE LIKE 5 shee's-Sneevt 5 Filed March 27 1946 @IEM zuaovn Azmuov m y www Oct. 31, 1950 C, B, ARNOLD ETAL 2,528,292

GASEOUS FLUID DISTRIBUTING SYSTEM FOR FURNACES AND THE LIKE 5 Sheets-Sheet 4 Filed March 27, i946 NVENTOR. CHARLES B. AR NOLD.

ATTORNEYS.

NQRMAL PosrrloN How/1 zo F. LAWRENCE.

Oct. 3l, 1950 Filed March 27, 1946 C. B. ARNOLD El' AL GASEOUS FLUID DISTRIBUTING SYSTEM FOR FURNACES AND THE LIKE 5 Sheets-Sheet 5 INVENTORS. CHARLES B ARNOLD.

WARD I". LAWRENCE.

ATTORNEYS.

Patented Oct. 31A, `1950V GASEOUS FLUID DISTRIBUTING SYSTEM FOR FURNACES AND THE LIKE Charlesl Arnold, Hempstead, N. Y., and Howard Y F.- Lawrence, Philadelphia, Pa., assignors to Consolidated' Edison Company of New York, fglnc., New York, N. Y., a corporation of New y York l. Application March 27, 1946, Serial No. 657,370

' 4 claims; (c1. 137-152) `rIhisinvention relateslto" systems for distributingA fluids, in either'gaseousor liquid state,-from a common source to numerous outlets, and cornprisesmeans' for so regulatingthe flow of such .vr-fluidsv in-passing-throughsuch a system,` as auto- --i/matieally toV reduce the flow'in portionsof the system-where otherwise vthev flow would tend to become Ivexcessive, and compensatively to increase the flow proportionately .in other portions of the system.`

The invention finds-application in `heating and `.Ventilating systems,` air conditioning systems, etc.

It finds-particular application inv supplying air, under forced'-draftpressure, through `the grate Sareav of [large boiler-furnaces and theflike, especially-those ernployingautornatc stokers, and

vin accordance-with the *principles-f aforesaid, l"namely, automaticallyito reduce the air supply ito portionsv'of' -thewfuel' bed which! have become thin, and ithusimitiga'te the'tendenc'y forv such vthin portions to iburn out, while at the same time `to -coinp'ensativel-y increase theair supply to thedenser portions of thefuel-bedlwhere such increased air supply is1desired.` v

Y Fori' purposes of illustrating a specifici application of 'the invention, as describedmorein detail hereinafter, we have chosen a boiler and furnaceemploying a system for supplying air under forced draft, `and onevwhichisfprovided with an automaticstoker of the under-feed type. In this type of furnacegthe c oal is fed -to the bed of 'the iire bymeans of suitable powerdriven ramsand lpushers, and theairiunder-lpressure is supplied,

' forv the purpose of vsupportingA combustion, -through a series of tuyres arranged in banks alternatingfwithsaid` rams' and pusher`s. *The air is supplied by a" suitable blower to achamber underlyingthe pushers andthe tuyrespwhich is burning of the fuel thereat, and consequently areas, offering the least resistance to the draft,

will have a tendency to burn through more quickly than the dense areas, thus permitting an excessive rush of air through these thin portions of the fuel bed and thereby causing a reduction in the amount of air accessible in the denser areas. Moreover, this excessive rush of air through the thinner areas of the fuel bed produces a rapid causes abnormal and extremely rap-id burning vout to develop in these areas, thus allowing quantities ofl air in excess' of that required for proper combustionto passthrough them which is uneconomical. Conversely, the denser areas of the fuel bed do not receive a sufficient amount of air, sothat the fuel is not completely consumed `thereat, resulting in anunevenly burning fire,

which is quite unsatisfactory and uneconomical.

In applying the present invention to a boiler, furnace and Stoker of the type above mentioned, `the fire bed is theoretically divided into a plurality of approximately equal areas, and an automatic, air flow' controlling device is provided vvfor each of these areas which is interposed bevcommonly designated-as the wind-box, theair passing from the wind--boxI toi the tuyres and l through suitable apertures inthe tuyres 'to the "ofproperly effecting combustion.l Y

fuel-bed, where the oxygen in the air combines with the carbon'in the coal and. with the gases emanating from: the heated coal for the purpose In the 'operation of 'this typeof Stoker,l Vthere are times'when the coal-feeding apparatus fails 'to'distribute the coal-'uniformly over-the vtuyeres, wherebyf some portions of the fuelbed become unduly thin, while other-portions become cornf paratively dense. "Obviously, these'different por- 'tions of, the fuelbe'd having different thicknesses or densities will present resistance to the flow of air which vari'esin accordance'with;thefdensity ""of the fuel`- bed in these"differenti'.areas.I thin tween the tuyres and the wind-box of the furnace. These air flow controlling devices are mechanically interlinked in groups in such manner that air flow regulating actuation of any such device of a group will-produce proportional and compensating actuation of all other devices in said group.

More specifically, Yin accordance with the invention, the forced draft air from the wind-box is conveyed to the furnace through a series of vertically extending and horizontally spaced air ducts or iiues, each adapted to supply'the tuyres f over different areas of the fuelubed, adjacent suchair ducts being arranged to supply adjacent fuel bed areas, andfin aggregate to supply forced draft air over the entire grate area. These air ducts, sometimes called zone control boxes,

. are arranged in horizontally spaced alignment,

in successive rows across the Stoker, underneath the tuyeres, so that each air duct will supply a given number of tuyeres. Dampers are provided in :each of the air ducts which are rotatably mounted on lhorizontal shafts, and arranged to swing to either side of a normal position, as for exampleabout' 31* from the vertical, tofafully.

opened o r Vertical position (or to a stop of,V for f example, 15Yfrom the vertical) and to a fully Vclosed position of, for example, about 28 from the horizontal. The dampers ofmthejsuc'cessive air du'cts'infany givenrow arearran'ged to swing alternately clockwise'and` counter-clockwise to amazes close, for reasons explained hereinafter. Each damper has affixed thereto a weighted lever arm which tends to maintain the associated damper in its normal position aforesaid. Also there is secured to each damper shaft and the aforementioned weighted lever arm an operating arm, at the extremity of which there is fulcrumed or pivotally supported at its midpoint for rotation about a horizontal axis, a control lever. 'Ihe control levers of adjacent air ducts in a given row are interconnected by horizontally extending link members which are pin-connected to the control levers at their extremities, in such a manner that one end of each control lever is pinconnected by a horizontal link member to the control lever next adjacent on one side thereof, while the other end of said control lever is similarly connected to the control lever next adjacent on the opposite side thereof. This mode of mechanical interlinking extends throughout all control levers in a given row of air ducts, with the exception that the horizontal link member extending from one end of each of the control levers in the terminal air ducts of any given row, is pin-connected to a fixed support. of this mechanical interlinking of the successive dampers in a given row of air ducts, coupled with the arrangement aforesaid whereby the successive dampers are mounted to swing alternately clockwise and counterclockwise to close, rotary movements of any damper in the row will be transmitted to all other dampers in the row in such manner asproportionately to adjust the same in compensating fashion. That is to say, if one damper tends toA be rotated toward the closed position, the interconnected control members and link members operate in such manner as proportionately to rotate all other dampers toward the open position.

When the air flows through the various ducts of a given row are uniform, the dampers will assume, by virtue of their weighted arms aforesaid, their aforesaid normal positions intermediate between the closed and fully opened positions, and all pneumatic forces on the dampers I will be maintained in balance by virtue of the aforesaid interconnecting linkages, which cause the forces on each damper to be balanced against the forces on each of the other dampers. When, however, due to localized weaknesses of the fuel bed, the air which flows through any particular -given damper are equal to all the forces acting on each of the other dampers. In accomplishing this result, the rate of air flow through the ducts feeding weakened fuel bed sections is actually reduced below the rate of air flow through normal sections of the fuel bed, thereby permitting the subsequent building up of the fuel bed resistance in such weakened sections, after which the dampers-return to their normal positions.

This tendency of a damper, in accordance with the invention, to close down by passage of By virtue air, under forced draft, around it, is brought about by venturi action as follows: As stated above, the damper is normally inclined at an angle of about 31 to the vertical, i. e., to the direction of the air duct, whereby the damper, in conjunction with the duct wall toward which it is inclined, constitutes what is, in effect, a venturi tube. Accordingly, as the air, under forced draft pressure, passes along the lower face of the damper from its inlet to its outlet edge, its velocity progressively increases. This progressive increase in velocity of air flow across the lower damper face produces a corresponding progressive decrease in static pressure acting on the lower face of the damper, in passing from its inlet to its outlet edge. In consequence, the total static pressure on the lower face of the outlet half of the damper becomes less than that on the lower face of the inlet half, thereby tending to rotate the damper toward its closed position. The action above described is enhanced by the portion of the air flow in the duct which passes between the inlet edge of the damper and the duct wall adjacent thereto, since this portion of the air ow is accelerated rapidly along the upper face of the inlet half of damper after it has passed the constriction formed by the inlet edge of the damper and the adjacent duct wall. On the other hand, as the damper is rotated toward its closed position by the pneumatic forces above described, the total air flow in the duct is correspondingly decreased, ih consequence of which the pneumatic forces tending to close down the damper are likewise correspondingly decreased. Due to these opposing tendencies, the damper will not ordinarily close down completely as a result of an increase in total air flow through the duct from an initial state of equilibrium, but will be rotated sufficiently toward its closed position to establish a new condition of equilibrium in which the total Vair flow through the duct is reduced below that of the aforesaid initial state of equilibrium.

Referring to the drawings:

Figure 1 is a longitudinal sectional plan view of a furnace embodying the novel features of the invention, this section being taken just above the grate and looking down on the grate.

Figure 2 is a partial sectional elevation through one of the tuyre banks of the furnace as taken at 2-2 of Figure l, these tuyre banks being divided` into zones supplied with forced draft through damper-controlled air ducts in accordance with the present invention, which are also shown in sectional elevation in the drawing. Figure 2a is a more or less schematic view similar to Figure 2, but including a blower, and duct connections therefrom for supplying air under forced draft to the vertical air ducts of Figure 2.

Figure 3 is an elevation taken at 3 3 of Figure 2 and showing a row of the damper-controlled air ducts or zone control boxes, with their interconnecting linkages as above described,

Figure 4 is a schematic showing of the interlinked, damper-controlled system of Figure 3, and illustrative of its mode of operation.

Figure 5 is an enlarged fragmentary view in side elevation of one of the intermediate air ducts or zone control boxes of a given row, illustrative of the mounting of the damper and associated linkage mechanism therefore; while Figure 6 is a sectional elevationv thereof taken substantially at 6 6 of Figure 5.

Figure '7 is an enlarged fragmentary view in side elevation of one of the terminal air ducts or zone controlboxes"of a given row,..showing the 'damper and" associated linkage mechanism, andthemanner inwhich the .'endlinkage of a given row is' :pivotally 'secured' to' a 'stationary support; while' Figure 8' isa sectional plan view thereof takenatY 848 'of Figure 7.

Figure 9 is'a`fragmentary viewinaxial section through one end of .the damper shaft, taken 'at 9+9 of' Figure 7i and'illustrating; the assembly thereon. of therweighted lever'arm'andthe operating arm Y'or' eccentric, on` whichlatter' the control lever or linkage mechanism isfulcrumed;

whileFi'gure '10v is a .viewiin front' elevation of the Figure 9 assembly.

Figures 11 and 12 are:l detail plan views of quadrant.members,"shown in assembly' in. Figures 9v and `10,.`and'providing a means for-lad- 'justably setting the'zclock'wise and counterclockwise i damper respectively.

"Figure v,13 is an' enlarged .fragmentary view corresponding toFigure 5;.b'ut showing the dam- Vper'in its closed position; ,while Figure14 is a similar 'view oil two adjacent air-ducts, in one v of which the damper` is operated toltheclesed position, whereas' inthe adjacent air"du'ct"'the "damper is concurrently actuated toward. Iits opened position` byA the' interconnecting linkage mechanism.

As illustratedin Figs; 1`, 2 and 2a, the furnace embodying the novel features of the invention, comprises a front wall I and side walls`2 2, dening a" iire`bed generally indicated. Vat 3, and comprising spaced r'owsof tuyre banks, as at 4, alternating with automatically actuated coalfeeding units or retorts, as at" 5. Eachv ofthe tuyre banks includes a pair of side walls, as at E, suitably mounted inthe furnace, and each 'tuyre bank comprisesa.series of tuyre units, 4 as at 1, of the usual construction, embodying spaced air outlets, as at 8,.Fig. V2, which comwithin the tuyre Each of. thev tuyre banks" I' is divided into a series of zones, such as A toD inclusive, by means OtmetalpartitiOns such 'as"I2, I3, Fig.. 2, formmunicate, with air passages, suchas 9, formed ing funnel-shaped, passageways communicating' at their bases withah ducts or flues, such as I4,

"oflthe successive tuyre banks areY arranged, for thisjpurposein spaced. parallel rows, such .as Ida to. |42, and 15aY vto'f'I 5i,across the stokerunderneath'the tuyre banks, so that,'as above stated,

each air` duct willf supplyair. .under forced .draft to a'different .and-corresponding. numberof tuyres, comprising in aggregate. allY of. the tuyresfltwill'also be. noted, for example, that the rst row of air ducts Illa to Mi. inclusive supplies air under forced draft tothe portions of. the successive tuyrebanks'which are ,locatedin `zone A;

.similarly the second -row of airfductsY I.5a to |52' invided 'Wi'th a damper, as ati 1.8 I9, Fig.v 2, which,

as shown. in'detail at. I8v in,Figs'.` 5, .6.81and 13, is

kmounted ona shaft'ZIla extendingthroughaper- K6 .turesinthe end walls Il of the duct, andjournaledfto" angle plates such as"2I, mounted in spaced relation tctheduct end walls I'I by means of other angle members, such as '22, which are welded, riveted or otherwise secured to the duct side walls I5. The damper I8V is thus rotatable about a` horizontalv axis between a fully closed position of `about A28""frornthe horizontal, as indicated at ISA', Fig. 5, and a fully opened position 10 of about 1'5" from the vertical, as indicated at I-SB, Fig. 5.` For limiting rotation of the damper inthe direction of opening, inwardly projecting "studs, as at' 23, are appropriately securedto the duct end walls `I'I;. while the side walls I6 of the duct serve to limit rotary movements of the damper in the direction of closing,l in the manner shown at 18A, Fig. 5. The damper is is so mounted, as explained below, as normally to maintain a normal inclination of about 31 from 20 the vertical, as shown'at I8 in Fig. 5,

Asabove explained, the air ductsvare'disposed, equally spaced, in rows extendingV transversely across the stoker underneath the tuyres, as indicated` at ida-lei and ld-|51, etc., Fig. 1.Y Fig. 3 illustrates such a row of air ducts, as viewed in side elevation looking in the direction of 3-3of Fig. 2, to assure eq-ual spacing .of the ducts,-they are -rnounted in equally spaced, rectangularly ynotchedportions 25 of alignmentbars, such as {iO/"2d, Figs. 2 and 3, on which the air. ducts are supported. within the wind-box. .Still referringy to Fig. 3, the dampers, such. as lila, |5819, etc..of the successive air ducts Ilia, Ilib, etc. are arranged, asindicated, to swing alternately in clockwise and A counter-clockwise directions, respectively, for closing. Figi.. Salso shows .the aforesaid mechanical linterlinkages extending between Vthe successive hampers, whereby. rotary movements of any one are oppositely and compensatively transmitted to .40 all of the others, which interlinkages, however, are best explained by referenceto the detail drawings of Figs. 5 .to 12 inc. Y

Referring tothese detaildrawings, one end of eachdamper shaft 20a is provided with a collar ...4512i keyed thereto by a dowel,` as at 28. Mounted von the shaft adjacentto and welded on thecollar 2'I.is aquadrant member, such as that shown at -29 in Fig. 11, or vthat shown'at 3D in Fig. 12, the particular type of quadrant member employed for any particular damper depending on Whether the damper is-to be arranged for counter-clock- .-wiseor clockwise rotation Afor closing. Where vthe damper is to be rotated counter-clockwise for closing, the quadrant member 29 of Fig. 11 is employed, and, conversely, the quadrant member 3|) of Fig. l2-wherevtherdarnper is to rotate clockwise l for closing. It will be noted that each of these Vquadrant members is provided with a rearwardly extending collar portion 3| integral therewith,

50. which is dril1ed,as atv 32, for mounting on shaft 23a. Also,-eachquadrantmember is provided adjacent its-lower periphery with a series of .....arcuately spaced holes 33, Fig. 1l, or 34, Fig. 12, the lowermost holeof the series being in .vertical h5 .alignment with the shaft aperture-32, with the series of holes extending to the left, as at 33, from the vertical for the counter-clockwise type of quadrant, and extending to the right, as at 3d, for the clockwise typeof quadrant. The quadf rant member is initially assembled on the damper shaft 20a withits collar portion 3| abutting the dowelled shaft collar 21 and welded thereto.V The damper |8-is thereupon adjusted to its desired .normal position of about 31 from the vertical, .Q while maintaining'.therquadrant member with sesam the lowermost hole in the arcuate group 33 or 34, in vertical alignment with the shaft aperture 32, whereupon the abutting collars 3| and 21 are welded together as at 21a.

Following the above assembly, there is slidably mounted on shaft 29a, an eccentric member 35, comprising a pair of elongated metal straps 36, 31 welded together, and suitably drilled, as at 38, Fig. 9, for slidable reception of shaft 20a. From the inner member 36 is suspended an arm 39 having a weight 4U removably secured thereon by means of a threaded portion and cooperating nut 4|, Fig. 6. The outer metal strap 37 is the operating arm for the control lever above referred to, and for this purpose has secured to the lower end thereof an outwardly projecting stud 42, terminating in a spindle 43, on which is pivotally mounted, at its midpoint, a control lever 44 held in place by means of a washer and cotter pin assembly 45.

Near its lower end, the eccentric member 35 is provided with a, single drilled hole, as at 46, whereby this aperture 46 in the eccentric member may .be rotatably aligned with any of the apertures 33 or 34 in the quadrant members 29 or 3U, and secured thereto in such alignment by means of a bolt and. associated. nut assembly 4l. Ordinarily, the eccentric member 35 will thus be secured to the quadrant member, employing for this purpose the loWermost hole of the arcuate series in the quadrant group, as illustrated for example in Fig. 5, whereby the weighted arm 39, 40 will normally maintain the entire `assembly in the position shown in Fig. 5, with the damper at the aforesaid angle of about 31 from the vertical, representing the normal inclination of the damper. In the event, however, that any particular lamper requires a somewhat different setting in relation to the other dampers of a given row of air ducts, in order to provide the proper operati`on for the entire series of dampers, the eccentric 35 may be secured in another of the arcuately spaced holes 33 or 34 of the quadrant members 29 or 30 or all dampers in any one zone of dampers may similarly be set for a greater or lesser normal opening than those in some other zone. It will be observed that, in consequence of the assembly above described, the weighted lever arm 36, 39, 45, the operating arm 3'! (comprising assembly 35) and the quadrant member 29 or 3B, are al1 integrally united to each other, and in turn rigidly secured to shaft 20a, to which the damper I8 is also rigidly secured, whereby all of these components rotate as a unit.

Referring to Figs. 3 and 5 to 8 inclusive, each control lever, such as 44, Figs. and 6, or 44a, 44h, 44o, etc., Fig. 3, has pin-connected thereto at its outer extremities, as at 48, 49, Figs. 5 and 6, link members, such as 5|), 5|, which extend in opposite horizontal directions respectively, to the corresponding control members of the next adjacent air ducts, situated on the opposite sides, respectively, of the duct in question, and similarly pin-connected to the extremities of the control levers thereat, in the manner shown in Fig. 3 by the successive link members 52h, 52e, 52d, etc. As there shown, this mode of interlinking the successive damper controls extends .throughout all air ducts Illa-|41 inclusive of a given row, with the exception of the terminal air ducts |4a and |42' at the opposite ends of a given row, the control members 44a and 441' of which have one extremity thereof pin-connected to a link member, such as 52a 0r 522', the opposite end of which is vpin-connected to a xed support, as at 53 or 54.

Fig.`- 7 illustrates, `in enlarged detail, the terminal link connection shown at the left in Fig. 3, and

vdraft supplied through the various air ducts of a given row, such as |411. to |4i inclusive, Fig. 3, will be substantially uniform, in consequence of which all of the dampers I8@ toA |82 inclusive will Vassume their normal positions, as at lil, Fig. 5,

and all of thev pneumatic forces on the dampers will be maintained in balance through the medium of the interlinked operating arms, such as 37,v Fig. 6, control levers, such as 44a to 441, Fig. 3, and horizontal link members, such as 52a to 52i etc., Fig. 3, which thereby adjust the forces on each damper to be balanced against the forces on each of the other dampers in any given row. When, however, due to localized weakness in the fuel ,bedv within an' area supplied by any given air duct or ducts, such as |4a, |4b, |40. etc., Fig. 3, theforced'draft air supplied through such duct or ducts is increased more than the rate of flow through the remaining ducts, the pneumatic forces acting on the dampers passing the increased rate of air ow, will increase in a direcv tion to close Vclown these dampers by pneumatic action', while proportionately opening the remaining dampers.

Thus, referring for example to Fig. 5, it will be observed that, since each damper thereof is norrnallryV in the inclined position indicated at i8, itforms in conjunction with the side wall |5 at the left oi the duct, what is'in effect a venturi tube, Whereby,fas the' rate of air ow through the duct increases, regions of diminished pressure occur at the constrictions 55 and 55a, in the air ue formed by the damper I8 and the side walls |6, whereby the ldamper' is rotated toward the closed position |8A. -As a resu1t of this action,

however, all of the other dampers in the row are compensatively and proportionately opened by virtue of the mechanical interlinking of the dampers as a-bove described. Equalization of forces between dampers is reestablished when all closing dampers have moved suii'lciently to reduce the pneumatic forces acting on them to values such thattheforces on the closing dampers are again in equilibrium with the pneumatic forces on all other dampers in their new positions. i Fig. 4 illustrates diagrammatically the movements of the various dampers and linkage mechanisms in a given row, such as that of Fig. 3, when, for example, an increased rate of air vflow occurs in the two intermediate air ducts iisd, |4e. This increased air ow causes each of these dampers to be rotated toward their closed positions, which, as above explained, results in opposite directions opposite directions of rotation thereof for adjacent'dampers, since one damper |401 must rotate counter-clockwise to close, while the adjacent damper |4e must rotate clockwise to close. In consequence of this opposite rotation 'of the dampers in the air ducts |411, |4e toward i i i A comparison of Figs. and 13 illustrates the relative movements which occur in the operating arm 3l, control lever 44, weighted arm 39, 40 and horizontal linkage mechanisms 5D, 5|, when the damper I8 is operated from its normal position of Fig. 5, to its fully closed position of Fig. 13.

In a similar manner, Fig. 14 illustrates, in enlarged View, the linkage movements which occur in air ducts I4c and ldd of Fig. 3, when the two intermediate ducts Md and Me thereof are actuated to their closed positions, as illustrated diagrammatically in Fig. 4, like elements being similarly designated in Figs. 3 and 14. It will be observed, referring to Fig. 14, that when the damper [8d is operated to its fully closed position, the adjacent damper |86 is not operated to its fully opened position, but is opened to such an extent along with dampers 14a and Mbof Fig. 3 that the forces on all dampers will be balanced.

We claim:

1. In combination: a plurality of spaced, iluid passageways; a baille in each said passageway rotatably mounted on a shaft intermediate opposite edges of said baille, and adapting said baille to be rotated between closed and opened positions; means normally positioning successive bailles in oppositely inclined relation in said passageways respectively, and intermediate their open and closed positions, whereby Vsaid bailles are rotatable to their closed positions .alternately clockwise and counterclockwise by venturi action produced by fluid flowing between such bailles and the walls of the passages associated therewith; a lug keyed to each said shaft; a first group of link members individual to and centrally pivoted to the ends of said lugs respectively; .and other link members pivotally interconnecting the opposite ends respectively of adjacent said first link members, and in opposite directions therefrom respectively, whereby rotary movements of any said baille are oppositely transmitted to the remaining said bailles, and whereby unequal rates of fluid flow through said passage- Ways compensatively adjust said bailles from one state of equilibrium to another.

2. In combination: a row of substantially equally spaced and vertically arranged fluid passageways; a baille in each said passageway rotatably mounted on a shaft intermediate oppo- .site edges of said baille, and adapting said baille f to be rotated between opened and closed positions; `a weighted member keyed to each said shaft for normally maintaining the associated baille in an inclined position relative to the direction of said passageway, and intermediate between said .opened and closed positions; the successive bailles of said row being arranged to rotate alternately clockwise and counter-clockwise to close by venturi action produced by fluid flowing between such bailles and the walls of the passages associated therewith; a lug keyed to each said shaft; la ilrst group of link members individual to said lugs, and centrally pivoted to the ends of said lugs respectively; and additional link members pivotally interconnecting the orpposite ends respectively of adjacent said first link members, and in opposite directions therefrom respectively, whereby rotary movements of any said baille are oppositely transmitted to the remaining said bailles, and whereby unequal rates of fluid flow through said passageways tend, by Venturi action, to actuate certain of said bailles toward their closed positions, and compensatively to actuate the remaining said bailles toward their opened positions.

3. In combination: a row of spaced, substantially parallel, iluid passageways; a baille in each said passageway rotatably mounted on a shaft intermediate, opposite edges of said baille, and adapting the same to be rotated between closed andopened positions, said shaft being substantially perpendicular to the direction of the associated passageway; means normally maintaining each said baille in inclined relation relative to the direction of the associated passageway, and intermediate between said opened and closed positions; the successive bailles in said row being arranged to rotate alternately clockwise and counter-clockwise to close by Venturi action produced by fluid ilowing between such bailles and the Walls of the passages associated therewith; a lug keyed to each said shaft; a first group of link members individual to said lugs and centrally pivoted to the ends thereof respectively; and other link members pivotally interconnecting the opposite ends respectively of adjacent said first link members, and in opposite directions therefrom respectively, whereby rotary movements of said baille are oppositely transmitted to the remaining said bailles, thereby automatically and compensatively to adjust Said bailles for other-wise unequal rates of fluid flow through said passageways.

4. In combination: a plurality of fluid passageways; means for supplying fluid to said passageways under pressure from -a common source; a baille in each said passageway rotatably mounted on a shaft intermediate opposite edges of said baille, said shaft being substantially perpendicular to the direction of said passageway, and said baille being adapted for rotation thereon between closed and opened positions, inclined to the direction of said passageway; means normally positioning successive bailles in oppositely inclined relation in said passageways respectively, and intermediate their open and closed positions, whereby said bailles .are rotatable to their closed positions alternately clockwise and counterclockwise by Venturi action produced by fluid flowing between such bailles and the Iwalls of the passages associated therewith; a lever arm keyed to each said shaft; and means mechanically interconnecting said lever arms whereby rotary movements of any said baille are oppositely transmitted to the remaining said bailles, and whereby unequal rates of fluid flow through said passageways tend, by Venturi action, to actuate certain of said bailles toward their closed positions, and compensatively to actuate the remaining said baffles toward their opened positions.

CHARLES B. ARNOLD. HOWARD F. LAWRENCE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 323,539 Smith Aug. 4, 1885 1,268,424 Beers June 4, 1918 1,745,238 Alpern Jan. 28,- 1930 2,010,694 Jones Aug. 6, 1935 2,255,681 Sauter Sept. `9, 1941 2,375,479 Langhaar May 8, 1945 FOREIGN PATENTS Number Country Date 23,103 Great Britain of 1907 

